Studies of the floral biology of neotropical Nymphaeaceae. 3

Abstract

A field study of the floral biology of two species of Nymphaea (Nymphaeaceae) wp.s made. N. rudgeana G.F.W. Meyer, a night flowering species, was studied around Manaus and Belém. It is visited by the scarab beetle Cyclocephala castanea Oliv. in the Manaus vicinity and by C. verticalis Burm. in the Belém vicinity. N. rudgeana is protogynous and cross-pollination is quite frequent. N. ampla (Salisb.) DC., a day flowering species, was studied near Salvador, Bahia. This species is visited by the bee species Trigona spinipes. N. ampla is not protogynous and is largely self-fertilized, although a small amount of cross-fertilization may occur through the activity of the Trígona bees.

The evolution of floral biology in basal angiosperms

“…Of the 23 families with at least partly bisexual flowers, 21 are protogynous judging from a check of the original literature for 176 species; the dichogamy patterns of the other two (Gomortegaceae and Hernandiaceae) are unknown. Adichogamy has only been reported for three derived beetle-pollinated Nymphaea species (Prance & Anderson 1976;Wiersema 1988;Borsch et al 2008) and for Piper regnelli (de Figueiredo & Sazima 2000). The problem here is that beetle-pollinated flowers sometimes open only incompletely in the first phase of anthesis, and thus the early functional female phase may just not have been noticed properly.…”

“…The most radical method is that the flowers close after the female phase and open again in the male phase. This is known from a number of families (also related to day-night rhythm), such as Cabombaceae (Osborn & Schneider 1988), Nymphaeaceae (HeslopHarrison 1955a,b;Valla & Cirino 1972;Prance & Arias 1975;Prance & Anderson 1976;Schneider & Chaney 1981), some Magnoliaceae (Heiser 1962;McDaniel 1966;Thien 1974;Kikuzawa & Mizui 1990), Annonaceae (Silberbauer-Gottsberger et al 2003;Ratnayake et al 2006Ratnayake et al , 2007, and Winteraceae (Thien 1980;Thien et al 1985). Austrobaileyaceae and a number of families in Magnoliales and Laurales have an unusual kind of organ, inner staminodes that cover the stigma at the end of the female phase in some groups such as Degeneriaceae, Himantandraceae, Eupomatiaceae, Calycanthaceae and Atherospermataceae (Endress 1984b(Endress , 1992).…”

Ancestral traits and specializations in the flowers of the basal grade of living angiosperms

“…The second set includes partial syncarpy, an increase in ovule number, and prominent lateral laminar diffuse placentation (presumed to be related to the dorsal placentation seen in Cabombaceae), combined with a switch from carpel sealing by secretion to sealing by postgenital fusion. In pollination biology there is a shift from generalized pollination to pollination by large beetles (Cyclocephala Dejean, Scarabaeidae; Prance & Arias, 1975;Prance & Anderson, 1977), concomitant with a change from diurnal to nocturnal flowering, which occurs in Victoria and several tropical Nymphaea species. The clades with these extreme specializations are highly nested in the family and therefore relatively young (Yoo & al., 2005;Borsch & al., 2008;, although fossil evidence for the presence of crown group Nymphaeaceae in the Early Cretaceous (Friis & al., 2009;Doyle & Endress, 2014) indicates that diversification of the family was not as recent as inferred by the molecular dating analysis of Yoo & al.…”

Pollen tube growth and the pollen-tube pathway of Nymphaea odorata (Nymphaeaceae)

“…Male phase begins with dehiscence of inner anthers on second-day N. odorata flowers. In contrast, in at least two tropical species of Nymphaea the outer anthers open first and they open on first-day flowers (Prance & Anderson, 1976;Orban & Bouharmont, 1995;Endress, 2001).…”